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2018 Hurricane Briefing for the Institute for Catastrophic Loss Reduction

Bob Robichaud Warning Preparedness Meteorologist Canadian Hurricane Centre Contents

• Tropical 101

• Review of the 2017 Hurricane Season

• Outlook for the 2018 Hurricane Season

• Sources of information for monitoring hurricanes Tropical Cyclones 101 Tropical Cyclones • Tropical is the generic term for such storms as hurricanes, tropical storms, typhoons, etc….

• They form over the warm tropical waters around the world

• Tropical cyclones serve the purpose of redistributing energy stored in the ocean into the atmosphere

All hurricane tracks:1842-2017 Hurricane Climatology Hurricane Origin and Track by Month

June July

August September

October November Checklist for formation

• Warm ocean waters that is sufficiently deep

• Unstable atmosphere

• High humidity in the lower levels of the atmosphere

• A minimum distance of at least 500 km from the equator

• A pre-existing near- surface disturbance

• Low Tropical Cyclone – Nature’s Heat Engine Tropical Cyclone Classification

Hurricane Major Hurricane

Tropical Storm Category 1 Category 2 Category 3 Category 4 Category 5

Wind > 63 km/h 119-153 km/h 154-177 km/h 178-208 km/h 209-251 km/h Wind > 252 km/h

Debby Hermine Juan Joaquin Floyd Irma (2012) (2016) (2003) (2015) (1999) (2017

Allison Isaac Arthur Gaston Harvey Patricia (2001) (2012) (2014) (2016) (2017) (2015)

Minimal Damage Some Damage Extensive Devastating Catastrophic Catastrophic Damage Damage Damage Damage Tropical vs. Non-Tropical Storms Tropical Cyclone Non-Tropical Cyclone

• Fueled by the warm water • Fueled by the horizontal contrast in air temperature • Slow-moving • Generally faster-moving • Symmetrical • Asymmetric

Major 2017 Winter Storm January 2018 From Tropical to Post-Tropical

Wind Storm becomes post-tropical, Heavy rain moving very fast, heavy rain Strongest winds on the left, strongest winds on the right

Storm size increases, rain begins to shift left of track Strengthens to a hurricane, moves slowly westward

Storm forms Storm starts to speed off up and curve northward Tropical Cyclone Hazards Hurricane Season 2017 in Review 2017 Hurricane Season 2017 Hurricane Season Storm Tracks 2017 Hurricane Season Storm Tracks Early start to hurricane season • First storm of the season was TS Arlene which formed on April 19th

• TS Bret and Cindy formed in June – no impact from Bret but Cindy resulted in 2 fatalities

• TS Don and Emily formed in July – no impact from Don but Emily resulted in flooding in southern part of

• In early August, Franklin became the first hurricane of 2017 although was short- lived and impacts were minimal

• formed in mid August but stayed offshore (Cat 2)

• Harvey started as a typical weak August tropical storm that affected the

• After some weakening Harvey began to re-intensify after crossing the Yucatan

• Harvey rapidly intensified into a category 4 August 25th making along the middle Texas coast

• Persistent heavy rains caused catastrophic flooding, and Harvey is the second-most costly hurricane in U.S. history, after accounting for inflation, behind only Katrina (2005) Hurricane Harvey

• Landfall along the Texas Gulf Coast late on August 25th as a Cat 4

• First Major Hurricane to make landfall in the U.S. since 2005

• Peak recorded wind speed of 229 km/h

• 57 reported tornadoes with Harvey

• Significant was also reported (as high as 2- 3 m)

Hurricane Harvey

• Very slow movement of the storm over the next few days resulted in extreme rainfall

• Harvey was the most significant tropical cyclone rainfall event in history

• The highest storm total rainfall report from Harvey was 1539 mm

• Radar estimates indicated that the peak rainfall could be in the 1600 to 1800 mm range

• The rainfall was also extreme in areal coverage

Hurricane Harvey

Hurricane Harvey Rainfall Comparisons

millimetres Hurricane Harvey - Impacts

• At least 68 people died from the direct effects of the storm in Texas

• Over 300,00 structures were flooded

• Up to 500,000 cars were flooded

• 40,000 people evacuated or took refuge

• About 30,000 water rescues were reported

• 336,000 customers lost power

• Oil refineries were shut down for extended periods Hurricane Harvey - Impacts

• About 75% of the flood damage occurred OUTSIDE the 100-year flood zone

• 80% of flood victims DID NOT have flood insurance

• Preliminary estimates for damage costs are at $125 B U.S.

• Recovery continues Hurricane Irma

• Developed off the coast of Africa in late August and became a hurricane early on August 31st

• Eventually reached Cat 5 with winds of 290 km/h

• Landfall in and St Martin at peak intensity

• Two more as Cat 5 – , and one as Cat 4 in Bahamas

Hurricane Irma

• Irma made its 6th landfall in the Lower Florida Keys on September 10th as a Cat 4 Hurricane

• Final landfall was near Marco Island before the storm crossed the spine of Florida

• Peak wind was 257 km/h (unofficial report of 320 km/h)

• Peak wind in the U.S. was 193 km/h in the Florida Keys

• 21 tornadoes were reported

Hurricane Irma • Positive storm surge was reported at several location in the and in the U.S. • Offshore winds on the northern side of Irma’s circulation initially caused a negative storm surge and receding water levels along Florida’s West Coast • Some normally submerged areas went virtually dry, allowing people to walk out onto the sea or bay floor • This is a very dangerous situation as the water will eventually rise and rise rapidly Hurricane Irma - Impacts • 129 fatalities, 44 direct and 85 indirect

• About $50 B U.S. in damages

• Widespread devastation in the Caribbean

• Total destruction on the island of Barbuda

• Entire island was left the island – totally uninhabited for the first time in 300 years

• 150,000 homes damaged in Cuba

• Lower Florida Keys were devastated

Hurricane Irma - Impacts

• Largest evacuation in U.S. history (6.8 Million)

• Significant flooding along the east coast of Florida

• Combination of storm surge and heavy rain resulted in worst flooding in Jacksonville in over 225 years

• Wind impacts extended into Georgia and the Carolinas

• Extreme focus on the track resulted in some misinterpretation of the forecast for Florida

Hurricane Season 2017 Continues

• Jose formed in early September and intensified rapidly to Cat 4 then meandered off the coast of New England for a few days

• Katia was a short-live Cat 2 hurricane that formed in the Gulf of

• Lee formed in mid- September and reached Cat 3 but stayed offshore

Katia Irma Jose • Maria also formed over the central Atlantic in mid- September

• Rapidly intensified to a major hurricane eventually reaching Cat 5 with winds 282 km/h

• Ravaged the island of with winds of 269 km/h

• Direct hit on with winds of 250 km/h

• Approached Carolina coast before making a hard right turn Hurricane Maria - Impacts • 112 fatalities direct fatalities, likely well over 1,000 indirect fatalities so far

• Dominica sustained catastrophic damage

• $90 billion USD in damage (3rd costliest hurricane in U.S. history)

• Electric grid was devastated (80% of utility poles were destroyed)

• Practically all cell phone service was lost and municipal water supplies were knocked out

• Recovery still very much ongoing today • Nate was a Cat 1 Hurricane that formed in early October and impacted and the U.S. Gulf Coast

• Close to 500 mm of rain reported in Central America

• 44 fatalities

• Flooding and mudslides in

• Heavy rain, flooding and storm surge were reported in the U.S.

• About $800 million in damage

Hurricane Season 2017 Continues

• Ophelia was a storm that formed in mid-October and became the final hurricane of 2017

• Ophelia reached Cat 3 and followed an odd track that brought it into as a strong Post-Tropical Storm

• Phillip was a late October TS – minimal impacts

• Finally Rina formed in early November. With Rina, 2017 became the only season with a named storm in every month 2017 Hurricane Season Summary • 2017 was an historic season with several new records set during the season – 7th most active year in the last 167 years

• 6 major hurricanes formed in 2017, the most since the hyperactive 2005 season

• Costliest year for hurricanes – $265 Billion

• 2nd (Harvey), 3rd (Irma) and 5th (Maria) costliest U.S hurricanes

• Five Category 5 landfalls

• Three Category 4 landfalls in the U.S in 26 days – only three in the previous 56 years!!

• First time the U.S. had two landfalling category 4 hurricanes the same year – Harvey and Irma

• Harvey set a new record for tropical cyclone-generated rainfall in the U.S. with 1539 mm

2017 Hurricane Season Summary

• 37 cases of rapid intensification (strengthening of the wind speed by at least 55 km/h in 24 hours) in 2017 – only 6 were correctly forecast by NHC

• Ophelia was the farthest east that an Atlantic major hurricane had ever been observed

Factors Influencing Hurricane Season

Water Wind Shear Multi-decadal Temperature cycle

Less More active Less active Average Current Water Temperature Current Water Temperature Latest Atlantic Pattern

Water temperatures are warmer than normal

Water temperatures are cooler than normal Factors Influencing Hurricane Season

Water Wind Shear Multi-decadal Temperature cycle

Less More active Less active Average Factors Affecting Hurricane Season

May 30, 2017 Factors Affecting Hurricane Season

May 31, 2018 El Niño forecast through hurricane season Factors Influencing Hurricane Season

Water Wind Shear Multi-decadal Temperature cycle

Less More active Less active Average 2018 Hurricane Season Outlook Entire Atlantic vs. CHC Response Zone

Based on the 30 year average, about 35-40% of the named storm that for in the Atlantic enter the CHC Response Zone List of Atlantic Storm Names Operational Response to Approaching Storms: Hurricane monitoring tools Hurricane Forecast Centres National Hurricane Centre - Canadian Hurricane Centre - Halifax

Detailed information from CHC starts about 72 hours BEFORE the storm crosses this line

NHC is the Regional Specialized CHC provides Canadians with Meteorological Center (RSMC) for the WMO meteorological information on hurricanes, RA-IV tropical storms and post-tropical storms Hurricane Weather Products - NHC

Graphical Tropical Weather Outlook Probability of Categories formation Low < 40% Medium 40-60% High >60%

https://www.nhc.noaa.gov/

• Track map with range of possible tracks (cone) • Wind speed probability map • Wind history • Time of arrival of tropical storm force winds • Surge and rainfall maps • Key messages graphic Hurricane Weather Products - CHC www.hurricanes.ca Hurricane Track Maps -All tracks will be displayed on the CHC hurricane track map - Blue tracks are CHC-issued tracks - Red tracks are NHC-issued tracks

Bulletin Structure 1) Summary information on initial position, intensity, motion 2) Public impacts • warnings broken down by hazard (wind, rainfall, surge/waves) 3) Marine impacts and warning Hurricane Weather Products Forecast Uncertainty – Track Error - Cone of uncertainty is constructed by superimposing position error at each forecast time - You must assume that the centre of the storm will track ANYWHERE within that cone - There is also a 33% chance the storm could track outside the cone 2018 Position Errors 120 hrs – 367 km - Keep in mind that 96 hrs – 280 km impacts could 72 hrs – 191 km extend well 48 hrs – 137 km outside the cone 24 hrs – 80 km 12 hrs – 48 km

….it only takes one storm to make it a bad year!